Vehicle seat with headrest movement responsive to seat back tilting

ABSTRACT

A tilting, adjustable passenger seat back is provided with an angularly adjustable upper headrest section which has tilting linkage and a hinge connection to the upper part of the seat back such that when the back is in a generally upright position, the headrest section is back and out of the way of a passenger&#39;s head and shoulders; however, when the seat back is moved to a recline position, the headrest section will rotate forward to provide support for the head while the passenger is in the recline position. A modified construction also has additional linkage which provides for a lumbar support that moves along with recline movement to be primarily effective to adjust seat back cushioning for upright positioning of the seat back and out of the way for the recline position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of copending application Ser.No. 520,311, filed Nov. 4, 1974, now U.S. Pat. No. 3,929,374.

The present invention relates to a special tilting seat backconstruction for a vehicle seat which provides an angularly adjustableheadrest section.

More particularly, the invention is directed to a tilting seat backarrangement where there is automatic movement of a headrest section tohave such section out of the way when the back is in a generally uprightposition and tilted forward for head support when the seat back is inthe recline position.

A further modification of the seat back has additional linkage to theheadrest adjustment means such that there is maximum lumbar support whenthe seat back is in the upward positions but minimal, or non-operative,when the seat back is in a recline position.

It is recognized that there are many types of linkages and operationsfor reclining the backs of passenger seats, as well as various types ofmechanically and pneumatically operated lumbar sections for a seat back;however, it is not believed that there are present designs or operationswhere there is a lumbar adjustment tied into the linkage for adjusting atilting headrest section for a reclining back vehicle seat. Also, knownheadrest adjustment means have been made responsive to the tilting ofboth the seat and back portions of a seat while, conversely, the presentheadrest tipping arrangement is responsive only to the recline of a seatback section.

In airplane and other vehicle passenger seating, it has been found thatheadrest sections of seat backs frequently impinge upon the shoulderand/or the head of a passenger, particularly where the occupant is aboveaverage in height. Thus, from a passenger comfort aspect, it ispreferable to have the headrest section out of the way while the seatback is in the generally upright positionings. On the other hand, it isdesirable to have the headrest section move slightly forward when theseat back is in a recline position. It appears that a seat occupantnaturally assumes a somewhat curved position when a seat back is put ina recline position and there is greater comfort by having a headrestsection that will be moved and tilted forward for the reclinepositionings. As a further advantage, the forward tilting of theheadrest section helps to provide more space to the rear of the seatupon seat back recline.

It may therefore be considered a principal object of this invention toprovide a seat back construction which has a separate tiltable upperheadrest section and integrated linkage means that will cause the latterto be in a straight extended, out-of-the-way position when the back isin the generally upright location but will be caused to tilt forwardwhen the seat back is being lowered to various recline positions.

It is a further object of the present invention to integrate additionallinkage means with the headrest tilting linkage members such that thelumbar portion of a seat back will have an outwardly projecting backsupport zone when the seat back is in the more upright positions andthen move into the seat back, or into a collapsed orientation, when theseat back is moved into the recline positionings. From a comfort aspect,it seems that a lumbar support or seat back projection is lessdesirable, or even undesirable to some passengers, when the seat back ismore or less fully reclined.

In one embodiment, the present invention provides in a vehicle passengerseat having a seat section, seat support framing and a reclining seatback, the improved construction to provide a movable headrest sectionthat comprises in combination, (a) an elongated tilting seat backsection having a hinged connection at its lower end to a fixed locationor non-moving seat support framing, (b) a relatively short tiltingheadrest section having a hinged connection from its lower portion tothe rearward part of the upper end portion of said seat back section andforming an extended portion for the latter, (c) a fixed length, stifflinking member connecting to a fixed position, non-translating, lowerpivot means on the non-moving seat support framing at a position spacedupwardly from said hinged connection for said back section, and saidlinking member extending upwardly to an upper pivot means on saidheadrest section which is spaced from and positioned forward of thehinged connection between the upper part of said seat back section andsaid headrest section, and (d) said linking member positioned to begenerally parallel to the tilting seat back section, such that as thelatter is tilted from a generally upright position to a recline positionthere is a resulting translation of the top end portion of the seat backsection relative to said upper pivot point means between said linkingmember and said headrest section and a resulting forward tilting of thelatter section with respect to the back section.

Typically, in a preferred arrangement, there will be two linking membersto the tiltable headrest section, with a linking member extending alongeach side of the seat back section and the upper and lower pivot pointsfor the linking member will be generally in line with the side framingof the seat back section such that straight, or relatively straight,linking members can be utilized to extend between the seat supportframing and the lower forward portions of the tilting headrest section.

In a modified arrangement, there can also be additional linkageextending outwardly from the two side linking members or from the lowerpivot point for such members and connecting pivot means from the sidesof the seat back framing such that there can be a transverse lumbarsupport bar which will move in and out with respect to the seat backsection and in a slight arcuate movement responsive to tilting movementsof the seat back section. For example, arm means at each end of thetransverse lumbar support member which pivotally connect to the samelower pivot points for the linking members and which also havelongitudinal slot means to accommodate fixed pin means from the seatback framing will provide for the translation of the transverse lumbarmember responsive to relative movement between the linking members andthe seat back framing as the seat back section is tilted. The lumbarsupport member, or bar, will be constructed and arranged so as to beembedded below the surface of the seat back cushioning at a zone whichwill be in the lumbar region of the seat occupant such that thecushioning and upholstery will be pushed outwardly to give back supportwhen the seat back is in a generally upright position and conversely,the support bar will be rotated and retracted a short distance withrespect to the seat back framing to in turn lessen its projection in thelumbar region as the seat back section is tilted into a reclineposition.

Reference to the accompanying drawing and the following descriptionthereof will assist in describing the present invention with respect toan adjustable headrest section and lumbar support means, as well as setforth additional advantageous features in connection therewith.

FIGS. 1 and 2 of the drawing illustrate diagrammatically the location ofpivot point means and linking means to effect the movement of anadjustable, tiltable headrest section responsive to seat back tilting.

FIGS. 3 and 4 of the drawing indicate diagrammatically how additionallinkage means in the lumbar region of a seat back section and betweenthe latter and the pivot point for the headrest linking means mayprovide for lumbar support adjustment responsive to seat back tilting.

Referring now particularly to FIGS. 1 and 2 of the drawing there isindicated in a diagrammatic manner fixed seat support framing 1 adaptedto hold seating means at 2 and a tilting seat back section 3, which inturn is provided with an extended movable headrest section 4. The seatback section 3 is illustrated as having side framing portions 5 whichpivotally, or hingedly, connect through pivot means 7 with bracket means8 on seat support framing 1. Thus, back section 3 will pivot about thepin means 7 when being lowered or raised in connection with reclinepositioning.

There is also indicated a hinged connection at 9 between the upper endportion of seat back framing 5 and a lower rearward portion of theheadrest section 4 such that the latter can be separately tilted withrespect to the seat back section 3. In addition, there will be a fixedlength linking member 10 extending between a pivot 11 which is locatedat an elevated portion of the seat support framing 1 and extends toanother upper pivot connection 12 at a lower forward portion of headrestsection 4. Thus, as may be seen from comparing the generally uprightback section positioning of FIG. 1 with a recline position in FIG. 2,there will be noted the relative movements between the fixed lengthlinking member 10 and the framing 5 for the seat back section 3 as thelatter pivots about hinge connection 7. The actual effect is that pivotconnection 12 is caused to be translated relative to the pivot or hingeconnection 9 when the back section 3 is reclined and the headrestsection 4 is caused to tilt forwardly with respect to the upper end ofseat back section 3. This arrangement provides the desired forwardtilting of the headrest as a seat occupant moves the seat back into arecline position and, conversely, when the seat back section is liftedto a generally upright position, such as in FIG. 1, the headrest section4 moves or tilts backwardly. As heretofore noted, it is generallydesired from a comfort angle, particularly for tall individuals, to havethe headrest section rearward and out of the way with respect to theseat occupant's head and shoulders when the seat back is in the "up"position.

It is to be understood that the framing and linkage indicated in FIGS. 1and 2 is diagrammatic and not limiting in any way with respect to themeans for accomplishing the tilting of the headrest section 4 responsiveto recline movements for the back section 3. Typically, a stiff linkingmember 10 will be provided on each side of the seat back section 3 suchthat the two members will extend generally parallel with the sideframing portions 5 for the seat back section.

A suitable hydraulic seat back adjustment lock or a mechanical seat backadjustment lock means will be connected between the seat support framing1 and the seat back framing 5 in a conventional manner, and is not shownin the present drawing. Such locking means may be placed under theseating 2 or in a generally vertical location along the lower portion ofthe seat back section 3, and again it is not intended to limit thepresent invention to the use of any one type of recline seat lock or toany one location for such lock means. Also, various types of cushioningand upholstery means may be provided in connection with the seating,seat back and headrest sections without effecting the scope of thepresent invention.

Referring now to FIG. 3 of the drawing, there is shown a somewhatenlarged view of the lower portion of the seat back section 3 with itslower side framing 5 and a linking member 10, each of which connect tothe fixed seat base portion 1 at the respective pivot connections 7 and11, all in the same manner as indicated in FIGS. 1 and 2 of the drawing.In addition to this linkage arrangement which operates the tiltableheadrest section, there is indicated in a modified embodiment that armmembers 13 at each end of a transverse lumbar support member 14 willprovide that the latter can be moved in and out with respect to the seatback framing 5. In this specific arrangement, the arm members 13 will befixedly connected to the ends of lumbar bar member 14 and there will bepivoted connections at 11, which is the same pivot point as for thelower ends of the linking members 10 which are being provided along eachside of the seat back section 3. In order to control the movement oftransverse bar member 14 there will also be a pin means 16 fixed to aprojecting portion 17 of each portion of side framing 5 which will passthrough a longitudinal slot 18 in each arm member 13. This arrangementprovides that any relative movement between linking members 10 and theside framing 5 will cause pin means 16 to bear against the sides ofslots 18 and, in turn, move arms 13 and the transverse bar 14.

As best shown in FIG. 4 of the drawing, there is indicated a tilting orrecline position for the seat back section 3 with respect to the seatingarea 2 as well as with respect to the seat support framing 1, and theresulting relative movement between linking member 10 and side framing 5such that the pin means at 16 attached to seat framing 5 will have movedupwardly with respect to the slot 18 and caused the upper portions ofarm members 13 and the lumbar bar 14 to move a short distance inwardlywith respect to the seat back framing. As a result, the lumbar member 14will reduce its pushing-out effect on back cushioning at 3'. Forcomparative purposes, it will be noted in FIG. 3 that the cushioning at3' is pushed outwardly in a lumbar supporting manner by reason of thelumbar member 14 being generally in its most outward position withrespect to seat back framing and linking members 10. Referring back toFIG. 4 of the drawing, it will be seen that the translated position forbar 14 permits the back cushioning at 3' in the lumbar region of theseat occupant to be returned to a generally normal position incomparison to the contour for the generally upright position for theseat back framing.

From a comfort aspect, as well as from the operation resulting from thelumbar linkage, the present special arrangement having the lumbar armmeans attaching the present linkage point for the headrest adjustmentmeans effects a resulting movement where the maximum lumbar support iseffected when the seat back section 3 is in the upright position and islessened when the seat back 3 is in the recline position. Various typesof cushioning arrangements may be provided to work in combination withthe moving bar means 14 such that the lumbar section of the seat backwill be pushed in and out from the bar movement; however, in certainembodiments, it may be advisable to utilize a generally rigid or stiffmember, such as a curved transverse member 19, to receive the movementand pressure from moving bar 14 and in turn translate the in-and-outmovement for the lumbar adjustment means into the cushioning at 3'.Typically foam padding will be utilized under upholstery coverings inthe seat back section of a vehicle passenger seat and at least a thinlayer of foam or padding will be utilized between the member 19, or thetransverse bar 14, and the outward surface of the seat back section at3'. Actually, the transverse support bar 14 may comprise two or moresections, or it need not be a straight member to provide a desiredlumbar support for a particular seat back configuration.

It is, of course, not intended to limit the present invention to thespecific types of pin means or pivot means between the lumbar supportarm members, the linking members and seat back framing, nor is itintended to limit the linkage to arm members of the particular designillustrated. In other words, various shapes, designs and configurationsmay be provided to effect the hinged linkage between the transverse barmeans and the linking or pivot connections to the seat frame members aslong as there is effected a similar movement resulting, in turn, fromthe relative longitudinal movements between the linking members and theseat back framing. The contours of the seat back and headrest framing,as well as for the attached padding, are also diagrammatic and can bemodified to suit appearance and desired comfort.

We claim as our invention:
 1. In a vehicle passenger seat having a seatsection, seat support framing and a reclining seat back, the improvedconstruction to provide a movable headrest section, which comprises incombination,a. an elongated tilting seat back section having a hingedconnection at its lower end to a fixed location on non-moving seatsupport framing, b. a relatively short tilting headrest section having ahinged connection from its lower portion to the rearward part of theupper end portion of said seat back section and forming an extendedportion for the latter, c. a fixed length, linking member connecting toa fixed position, non-translating, lower pivot means on the non-movingseat support framing at a position spaced upwardly from said hingedconnection for said back section, and said linking member extendingupwardly to an upper pivot means on said headrest section which isspaced from and positioned forward of the hinged connection between theupper part of said seat back section and said headrest section, d. saidlinking member positioned to be generally parallel to the tilting seatback section, such that as the latter is tilted from a generally uprightposition to a recline position there is a resulting translation of thetop end portion of the seat back section relative to said upper pivotpoint means between said linking member and said headrest section and aresulting forward tilting of the latter section with respect to the backsection, and e. a transverse lumbar support bar extending across thelower portion of said tilting seat back section in the zone of thelumbar region of a seat occupant, said support bar having fixedlyconnected arm members which extend downwardly to pivotally connect withthe seat support framing to thereby provide for an arcuate movement ofthe lumbar support bar about the connection points to the framing,longitudinal slot means being provided in the midportions of each of thearm members from the lumbar support bar, and fixed pin means from eachside portion of said seat back section being provided to extend throughthe respective slot means for said arm members whereby the tiltingmovement of the seat back section provides a relative movement betweenthe seat back framing and said arm members from the fixed pin means insaid slot means and there is a resulting translation of the connectinglumbar support bar to move with respect to the framing for the seat backsection.
 2. The seat of claim 1 further characterized in that a linkingmember is provided along each side portion of said seat back section forconnection to said headrest section, whereby the latter is operated fromtwo spaced linking members.
 3. The seat of claim 1 further characterizedin that a stiff but movable pressure distributing member is used incombination with said lumbar support bar to move seat back cushioning inand out responsive to the degree of projection of said lumbar supportbar.